1. Field of the Invention
The present invention relates to an image display device which includes an electron-emitting device and an anode substrate into which an electron beam from the electron-emitting device enters.
2. Description of the Related Art
As electron-emitting devices, there are an electron-emitting device of field emission (FE) type, an electron-emitting device of metal-insulator-metal (MIM) type, a surface-conduction electron-emitting device, and the like. Further, it has been proposed to constitute an image display device by providing anode electrodes opposed to an electron source that a large number of electron-emitting devices are disposed on an insulation substrate (see Japanese Patent Application Laid-Open Nos. H09-330676, 2000-215789, H03-020941, and 2003-068192).
In the above image display device, if an insulation portion of the insulation substrate on which the electron-emitting devices are disposed is exposed, a charge-up occurs on the exposed portion. Then, if any countermeasure against the charge-up is not adopted, there is a fear that it is difficult to stably drive the electron-emitting devices for a long time. Also, there is a fear that an electron emission characteristic changes time-dependently because an orbit of an electron beam emitted from the electron-emitting device is confused.
As disclosed in Japanese Patent Application Laid-Open No. 2003-068192, for example, it is necessary to provide, as a means for decreasing an influence due to the charge-up like this, a means for covering the surface of the insulation substrate with a high-resistance film such as an antistatic film.
Besides, each of Japanese Patent Application Laid-Open Nos. H09-330676, 2000-215789 and H03-020941 discloses such an image display device as described above.
Incidentally, if the antistatic film is disposed to prevent the surface of the insulation substrate from being charged, manufacturing processes of the image display device such as a film forming process, a patterning process and the like may often increase, and these process may be often complicated. In addition, there is a probability that, for example, if the material of the antistatic film is attached to the electron emission portion on the electron-emitting device, the electron emission characteristic changes.